Objective]To establish a new method for grafting ratio(GR) analysis of deoxycholic acid grafted chitosan(CS-DCA). [Methods]In this study, linear potentiometric titration(LPT) and 2,4,6-trinitrobenzenesulfonicacid(TNBS) were introduced to measure the GR of CS-DCA, using the 1H-nuclear magnetic resonance(1H-NMR) as reference, the results obtained by the two methods were analyzed to find a method to substitute H-NMR. [Results]There was no significant difference of the data determined by 1H-NMR and LPT(P>0.05), however, it didn't apply to 1H-NMR and TNBS(P<0.05), the results indicated that LPT had equivalent accuracy of 1H-NMR. Using 1H-NMR method as the standard reference, the relative error was no more than 3.8% for the method of LPT, and the maximum relative error for the method of TNBS was up to 12.8%, it meant that LPT had higher precision. [Conclusion]LPT is an economical, rapid and accurate method for the GR analysis of CS-DCA.

Objective To explore the practical method and teaching effect of problem-based learning (PBL) pattern in teaching of gastrointestinal disease for seven-year-program students during their internal medical probation.Methods The traditional pattern (gastrointestinal diseases) and PBL pattern (hepatobiliary diseases) were applied in these students to assess the teaching effects by exam scores and questionnaire.Results ① There was no significant difference between traditional training and PBL by exam scores (P＞0.05).② The PBL approach was widely accepted by students,which could contribute to the improvement of their learning motivation.It developed skills,including self-directed learning,summarizing,and clinical thinking capability and so on.Conclusion The PBL approach is a practical learning strategy that can improve the teaching effect; therefore it should be wildly practiced in future works.

Objectives To compare the migrating motor complex (MMC) in irritable bowel syndrome (IBS) patients with that in healthy controls. To explore whether discrete clustered contractions (DCC) are connected with abdominal pain in IBS patients. To improve the method of measuring gastroenteric motility (esp. jejunum). Methods By using 16-channel water-perfused catheter and manometry instruments, MMC in 16 cases of IBS with constipation (IBS-C), 18 cases of IBS with diarrhea (IBS-D) and 18 cases of healthy controls were monitored. Results The MMC durations of IBS-C and IBS-D patients were (127.5±25.5) min and (74.5±18.7) min, respectively. Comparision with those in the control group [(87.5±24.2) min]showed significant differences (P<0. 001). The contraction amplitudes of stage Ⅲ in different sites of IBS-C patients decreased significantly as compared with those in the controls [jejunum, (39.8±11.7) mm Hg vs. (61.1±14.1) mm Hg,P<0.001,1 mm Hg=0.133 kPa]. The propagation velocities of stage Ⅲ in different sites of IBS-C patients also decreased significantly as compared with those in the controls [jejunum, (1.8±0.9) cm/min vs. (2.6±0.8) cm/min,P<0.01].The contraction amplitudes of stage Ⅲ in different sites of IBS-D patients increased significantly as compared with those in the controls [jejunum, (69.7±20.5) mm Hg vs. (61.1±14.1) mm Hg, P<0.01]. The propagation velocities of stage Ⅲ in different sites of IBS-D patients also increased significantly as compared with those in the controls [jejunum, (4.1±2.5) cm/min vs. (2.6±0.8) cm/min, P < 0. 01]. DCC incidences of IBS-C and IBS-D were 87.5% and 88. 8%, respectively. Comperision with those in the normal group (83.3%) did not show significant difference (P>0.05). The prevalences of abnormal stage Ⅲ contractions (include disturbances and interferences of stage Ⅲ contractions) in IBS-C and IBS-D patients were 68.8% and 66. 7%, respectively; there were no significant differences between the two groups (P > 0. 05). However abnormal stage Ⅲ contractions did not exist in healthy controls. Conclusions (1) The MMC of IBS-C and IBS-D patients are changed, as compared with that in healthy people; this implies that small intestinal motility dysfunction is one of the pathogenetic factors of IBS. The abnormal stage Ⅲ contractions in jejunum may be a predominant change in IBS gastroenteric motility. (2) No apparent connection is found between DCC and pain in IBS. (3) By using 16-channel water-perfused catheter, we first carried out the method of monitoring jejunum contractions in China. Parameters of MMC in Chinese healthy people were investigated, esp. those of jejunum.

Objective: To investigate the changes of the intestinal mucosa-associated microbiota in the patients with ulcerative colitis (UC), and to explore their correlation with the clinical manifestations. Methods: From June to October 2016, at Gastrointestinal Endoscopy Center, the Second Affiliated Hospital of Xi′an Jiaotong University, 28 patients with UC and 16 healthy individuals who underwent colonoscopy examination were enrolled. The mucosa specimens of them were collected for fluorescent in situ hybridization (FISH). The bacterial flora were observed and counted, the correlation between the bacterial flora and the clinical manifestations were analyzed. Kruskal-Wallis test and Spearman rank correlation analysis were performed for statistical analysis. Results: Among 28 patients with UC, 16 were at active phase and 12 at remission phase. The number of total bacteria flora, Escherichia coli, Clostridium and Bacteroides of the active UC group and remission UC group were all more than those of healthy control group; however the number of Lactobacillus and Bifidobacteria were less than those of healthy control group, and the differences were statistically significant (χ²=23.34, 19.94; 23.40, 12.96; 23.39, 19.16; 23.32, 10.46; 23.19, 4.25; 18.94, 12.33; all P<0.05). The number of total bacteria flora, Escherichia coli and Bacteroides of the active UC group were more than those of the remission UC group, however the number of Lactobacillus and Bifidobacteria were less than those of the remission UC group, and the differences were statistically significant (χ²=7.32, 5.63, 5.62, 20.38 and 4.82; all P<0.05). In the patients with UC, the defecation frequency was positively correlated with the count of Bacteroides (r=0.459, P=0.014) and was negatively correlated with the count of Lactobacillus (r=-0.634, P<0.01). In UC patients, bloody stool, endoscopic appearance and total Mayo score were positively correlated with the counts of universal bacteria, Escherichia coli and Bacteroides (r=0.469, 0.403, 0.376; 0.604, 0.562, 0.475; 0.551, 0.463, 0.461; all P <0.05); and which were negatively correlated with Lactobacillus and Bifidobacteria (r=-0.570, -0.413; -0.899, -0.458; -0.862, -0.480; all P<0.05). The evaluation by the doctors was positively correlated with the counts of Escherichia coli (r=0.415, P=0.028), however was negatively correlated with Lactobacillus and Bifidobacteri (r=-0.841, -0.529; both P<0.01). Conclusion The intestinal microbiota have sigificantly changed in patients with UC which are correlated with some clinical manifestations of UC.